drivers/hid/usbhid/hiddev.c

   1 /*
   2  *  Copyright (c) 2001 Paul Stewart
   3  *  Copyright (c) 2001 Vojtech Pavlik
   4  *
   5  *  HID char devices, giving access to raw HID device events.
   6  *
   7  */
   8
   9 /*
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License as published by
  12  * the Free Software Foundation; either version 2 of the License, or
  13  * (at your option) any later version.
  14  *
  15  * This program is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18  * GNU General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU General Public License
  21  * along with this program; if not, write to the Free Software
  22  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  23  *
  24  * Should you need to contact me, the author, you can do so either by
  25  * e-mail - mail your message to Paul Stewart <stewart@wetlogic.net>
  26  */
  27
  28 #include <linux/poll.h>
  29 #include <linux/slab.h>
  30 #include <linux/module.h>
  31 #include <linux/init.h>
  32 #include <linux/input.h>
  33 #include <linux/usb.h>
  34 #include <linux/hid.h>
  35 #include <linux/hiddev.h>
  36 #include <linux/compat.h>
  37 #include "usbhid.h"
  38
  39 #ifdef CONFIG_USB_DYNAMIC_MINORS
  40 #define HIDDEV_MINOR_BASE       0
  41 #define HIDDEV_MINORS           256
  42 #else
  43 #define HIDDEV_MINOR_BASE       96
  44 #define HIDDEV_MINORS           16
  45 #endif
  46 #define HIDDEV_BUFFER_SIZE      2048
  47
  48 struct hiddev {
  49         int exist;
  50         int open;
  51         struct mutex existancelock;
  52         wait_queue_head_t wait;
  53         struct hid_device *hid;
  54         struct list_head list;
  55         spinlock_t list_lock;
  56 };
  57
  58 struct hiddev_list {
  59         struct hiddev_usage_ref buffer[HIDDEV_BUFFER_SIZE];
  60         int head;
  61         int tail;
  62         unsigned flags;
  63         struct fasync_struct *fasync;
  64         struct hiddev *hiddev;
  65         struct list_head node;
  66         struct mutex thread_lock;
  67 };
  68
  69 /*
  70  * Find a report, given the report's type and ID.  The ID can be specified
  71  * indirectly by REPORT_ID_FIRST (which returns the first report of the given
  72  * type) or by (REPORT_ID_NEXT | old_id), which returns the next report of the
  73  * given type which follows old_id.
  74  */
  75 static struct hid_report *
  76 hiddev_lookup_report(struct hid_device *hid, struct hiddev_report_info *rinfo)
  77 {
  78         unsigned int flags = rinfo->report_id & ~HID_REPORT_ID_MASK;
  79         unsigned int rid = rinfo->report_id & HID_REPORT_ID_MASK;
  80         struct hid_report_enum *report_enum;
  81         struct hid_report *report;
  82         struct list_head *list;
  83
  84         if (rinfo->report_type < HID_REPORT_TYPE_MIN ||
  85             rinfo->report_type > HID_REPORT_TYPE_MAX)
  86                 return NULL;
  87
  88         report_enum = hid->report_enum +
  89                 (rinfo->report_type - HID_REPORT_TYPE_MIN);
  90
  91         switch (flags) {
  92         case 0: /* Nothing to do -- report_id is already set correctly */
  93                 break;
  94
  95         case HID_REPORT_ID_FIRST:
  96                 if (list_empty(&report_enum->report_list))
  97                         return NULL;
  98
  99                 list = report_enum->report_list.next;
 100                 report = list_entry(list, struct hid_report, list);
 101                 rinfo->report_id = report->id;
 102                 break;
 103
 104         case HID_REPORT_ID_NEXT:
 105                 report = report_enum->report_id_hash[rid];
 106                 if (!report)
 107                         return NULL;
 108
 109                 list = report->list.next;
 110                 if (list == &report_enum->report_list)
 111                         return NULL;
 112
 113                 report = list_entry(list, struct hid_report, list);
 114                 rinfo->report_id = report->id;
 115                 break;
 116
 117         default:
 118                 return NULL;
 119         }
 120
 121         return report_enum->report_id_hash[rinfo->report_id];
 122 }
 123
 124 /*
 125  * Perform an exhaustive search of the report table for a usage, given its
 126  * type and usage id.
 127  */
 128 static struct hid_field *
 129 hiddev_lookup_usage(struct hid_device *hid, struct hiddev_usage_ref *uref)
 130 {
 131         int i, j;
 132         struct hid_report *report;
 133         struct hid_report_enum *report_enum;
 134         struct hid_field *field;
 135
 136         if (uref->report_type < HID_REPORT_TYPE_MIN ||
 137             uref->report_type > HID_REPORT_TYPE_MAX)
 138                 return NULL;
 139
 140         report_enum = hid->report_enum +
 141                 (uref->report_type - HID_REPORT_TYPE_MIN);
 142
 143         list_for_each_entry(report, &report_enum->report_list, list) {
 144                 for (i = 0; i < report->maxfield; i++) {
 145                         field = report->field[i];
 146                         for (j = 0; j < field->maxusage; j++) {
 147                                 if (field->usage[j].hid == uref->usage_code) {
 148                                         uref->report_id = report->id;
 149                                         uref->field_index = i;
 150                                         uref->usage_index = j;
 151                                         return field;
 152                                 }
 153                         }
 154                 }
 155         }
 156
 157         return NULL;
 158 }
 159
 160 static void hiddev_send_event(struct hid_device *hid,
 161                               struct hiddev_usage_ref *uref)
 162 {
 163         struct hiddev *hiddev = hid->hiddev;
 164         struct hiddev_list *list;
 165         unsigned long flags;
 166
 167         spin_lock_irqsave(&hiddev->list_lock, flags);
 168         list_for_each_entry(list, &hiddev->list, node) {
 169                 if (uref->field_index != HID_FIELD_INDEX_NONE ||
 170                     (list->flags & HIDDEV_FLAG_REPORT) != 0) {
 171                         list->buffer[list->head] = *uref;
 172                         list->head = (list->head + 1) &
 173                                 (HIDDEV_BUFFER_SIZE - 1);
 174                         kill_fasync(&list->fasync, SIGIO, POLL_IN);
 175                 }
 176         }
 177         spin_unlock_irqrestore(&hiddev->list_lock, flags);
 178
 179         wake_up_interruptible(&hiddev->wait);
 180 }
 181
 182 /*
 183  * This is where hid.c calls into hiddev to pass an event that occurred over
 184  * the interrupt pipe
 185  */
 186 void hiddev_hid_event(struct hid_device *hid, struct hid_field *field,
 187                       struct hid_usage *usage, __s32 value)
 188 {
 189         unsigned type = field->report_type;
 190         struct hiddev_usage_ref uref;
 191
 192         uref.report_type =
 193           (type == HID_INPUT_REPORT) ? HID_REPORT_TYPE_INPUT :
 194           ((type == HID_OUTPUT_REPORT) ? HID_REPORT_TYPE_OUTPUT :
 195            ((type == HID_FEATURE_REPORT) ? HID_REPORT_TYPE_FEATURE : 0));
 196         uref.report_id = field->report->id;
 197         uref.field_index = field->index;
 198         uref.usage_index = (usage - field->usage);
 199         uref.usage_code = usage->hid;
 200         uref.value = value;
 201
 202         hiddev_send_event(hid, &uref);
 203 }
 204 EXPORT_SYMBOL_GPL(hiddev_hid_event);
 205
 206 void hiddev_report_event(struct hid_device *hid, struct hid_report *report)
 207 {
 208         unsigned type = report->type;
 209         struct hiddev_usage_ref uref;
 210
 211         memset(&uref, 0, sizeof(uref));
 212         uref.report_type =
 213           (type == HID_INPUT_REPORT) ? HID_REPORT_TYPE_INPUT :
 214           ((type == HID_OUTPUT_REPORT) ? HID_REPORT_TYPE_OUTPUT :
 215            ((type == HID_FEATURE_REPORT) ? HID_REPORT_TYPE_FEATURE : 0));
 216         uref.report_id = report->id;
 217         uref.field_index = HID_FIELD_INDEX_NONE;
 218
 219         hiddev_send_event(hid, &uref);
 220 }
 221
 222 /*
 223  * fasync file op
 224  */
 225 static int hiddev_fasync(int fd, struct file *file, int on)
 226 {
 227         struct hiddev_list *list = file->private_data;
 228
 229         return fasync_helper(fd, file, on, &list->fasync);
 230 }
 231
 232
 233 /*
 234  * release file op
 235  */
 236 static int hiddev_release(struct inode * inode, struct file * file)
 237 {
 238         struct hiddev_list *list = file->private_data;
 239         unsigned long flags;
 240
 241         spin_lock_irqsave(&list->hiddev->list_lock, flags);
 242         list_del(&list->node);
 243         spin_unlock_irqrestore(&list->hiddev->list_lock, flags);
 244
 245         mutex_lock(&list->hiddev->existancelock);
 246         if (!--list->hiddev->open) {
 247                 if (list->hiddev->exist) {
 248                         usbhid_close(list->hiddev->hid);
 249                         usbhid_put_power(list->hiddev->hid);
 250                 } else {
 251                         kfree(list->hiddev);
 252                 }
 253         }
 254
 255         kfree(list);
 256         mutex_unlock(&list->hiddev->existancelock);
 257
 258         return 0;
 259 }
 260
 261 /*
 262  * open file op
 263  */
 264 static int hiddev_open(struct inode *inode, struct file *file)
 265 {
 266         struct hiddev_list *list;
 267         struct usb_interface *intf;
 268         struct hid_device *hid;
 269         struct hiddev *hiddev;
 270         int res;
 271
 272         intf = usbhid_find_interface(iminor(inode));
 273         if (!intf)
 274                 return -ENODEV;
 275         hid = usb_get_intfdata(intf);
 276         hiddev = hid->hiddev;
 277
 278         if (!(list = kzalloc(sizeof(struct hiddev_list), GFP_KERNEL)))
 279                 return -ENOMEM;
 280         mutex_init(&list->thread_lock);
 281         list->hiddev = hiddev;
 282         file->private_data = list;
 283
 284         /*
 285          * no need for locking because the USB major number
 286          * is shared which usbcore guards against disconnect
 287          */
 288         if (list->hiddev->exist) {
 289                 if (!list->hiddev->open++) {
 290                         res = usbhid_open(hiddev->hid);
 291                         if (res < 0) {
 292                                 res = -EIO;
 293                                 goto bail;
 294                         }
 295                 }
 296         } else {
 297                 res = -ENODEV;
 298                 goto bail;
 299         }
 300
 301         spin_lock_irq(&list->hiddev->list_lock);
 302         list_add_tail(&list->node, &hiddev->list);
 303         spin_unlock_irq(&list->hiddev->list_lock);
 304
 305         mutex_lock(&hiddev->existancelock);
 306         if (!list->hiddev->open++)
 307                 if (list->hiddev->exist) {
 308                         struct hid_device *hid = hiddev->hid;
 309                         res = usbhid_get_power(hid);
 310                         if (res < 0) {
 311                                 res = -EIO;
 312                                 goto bail_unlock;
 313                         }
 314                         usbhid_open(hid);
 315                 }
 316         mutex_unlock(&hiddev->existancelock);
 317         return 0;
 318 bail_unlock:
 319         mutex_unlock(&hiddev->existancelock);
 320 bail:
 321         file->private_data = NULL;
 322         kfree(list);
 323         return res;
 324 }
 325
 326 /*
 327  * "write" file op
 328  */
 329 static ssize_t hiddev_write(struct file * file, const char __user * buffer, size_t count, loff_t *ppos)
 330 {
 331         return -EINVAL;
 332 }
 333
 334 /*
 335  * "read" file op
 336  */
 337 static ssize_t hiddev_read(struct file * file, char __user * buffer, size_t count, loff_t *ppos)
 338 {
 339         DEFINE_WAIT(wait);
 340         struct hiddev_list *list = file->private_data;
 341         int event_size;
 342         int retval;
 343
 344         event_size = ((list->flags & HIDDEV_FLAG_UREF) != 0) ?
 345                 sizeof(struct hiddev_usage_ref) : sizeof(struct hiddev_event);
 346
 347         if (count < event_size)
 348                 return 0;
 349
 350         /* lock against other threads */
 351         retval = mutex_lock_interruptible(&list->thread_lock);
 352         if (retval)
 353                 return -ERESTARTSYS;
 354
 355         while (retval == 0) {
 356                 if (list->head == list->tail) {
 357                         prepare_to_wait(&list->hiddev->wait, &wait, TASK_INTERRUPTIBLE);
 358
 359                         while (list->head == list->tail) {
 360                                 if (file->f_flags & O_NONBLOCK) {
 361                                         retval = -EAGAIN;
 362                                         break;
 363                                 }
 364                                 if (signal_pending(current)) {
 365                                         retval = -ERESTARTSYS;
 366                                         break;
 367                                 }
 368                                 if (!list->hiddev->exist) {
 369                                         retval = -EIO;
 370                                         break;
 371                                 }
 372
 373                                 /* let O_NONBLOCK tasks run */
 374                                 mutex_unlock(&list->thread_lock);
 375                                 schedule();
 376                                 if (mutex_lock_interruptible(&list->thread_lock))
 377                                         return -EINTR;
 378                                 set_current_state(TASK_INTERRUPTIBLE);
 379                         }
 380                         finish_wait(&list->hiddev->wait, &wait);
 381
 382                 }
 383
 384                 if (retval) {
 385                         mutex_unlock(&list->thread_lock);
 386                         return retval;
 387                 }
 388
 389
 390                 while (list->head != list->tail &&
 391                        retval + event_size <= count) {
 392                         if ((list->flags & HIDDEV_FLAG_UREF) == 0) {
 393                                 if (list->buffer[list->tail].field_index != HID_FIELD_INDEX_NONE) {
 394                                         struct hiddev_event event;
 395
 396                                         event.hid = list->buffer[list->tail].usage_code;
 397                                         event.value = list->buffer[list->tail].value;
 398                                         if (copy_to_user(buffer + retval, &event, sizeof(struct hiddev_event))) {
 399                                                 mutex_unlock(&list->thread_lock);
 400                                                 return -EFAULT;
 401                                         }
 402                                         retval += sizeof(struct hiddev_event);
 403                                 }
 404                         } else {
 405                                 if (list->buffer[list->tail].field_index != HID_FIELD_INDEX_NONE ||
 406                                     (list->flags & HIDDEV_FLAG_REPORT) != 0) {
 407
 408                                         if (copy_to_user(buffer + retval, list->buffer + list->tail, sizeof(struct hiddev_usage_ref))) {
 409                                                 mutex_unlock(&list->thread_lock);
 410                                                 return -EFAULT;
 411                                         }
 412                                         retval += sizeof(struct hiddev_usage_ref);
 413                                 }
 414                         }
 415                         list->tail = (list->tail + 1) & (HIDDEV_BUFFER_SIZE - 1);
 416                 }
 417
 418         }
 419         mutex_unlock(&list->thread_lock);
 420
 421         return retval;
 422 }
 423
 424 /*
 425  * "poll" file op
 426  * No kernel lock - fine
 427  */
 428 static unsigned int hiddev_poll(struct file *file, poll_table *wait)
 429 {
 430         struct hiddev_list *list = file->private_data;
 431
 432         poll_wait(file, &list->hiddev->wait, wait);
 433         if (list->head != list->tail)
 434                 return POLLIN | POLLRDNORM;
 435         if (!list->hiddev->exist)
 436                 return POLLERR | POLLHUP;
 437         return 0;
 438 }
 439
 440 /*
 441  * "ioctl" file op
 442  */
 443 static noinline int hiddev_ioctl_usage(struct hiddev *hiddev, unsigned int cmd, void __user *user_arg)
 444 {
 445         struct hid_device *hid = hiddev->hid;
 446         struct hiddev_report_info rinfo;
 447         struct hiddev_usage_ref_multi *uref_multi = NULL;
 448         struct hiddev_usage_ref *uref;
 449         struct hid_report *report;
 450         struct hid_field *field;
 451         int i;
 452
 453         uref_multi = kmalloc(sizeof(struct hiddev_usage_ref_multi), GFP_KERNEL);
 454         if (!uref_multi)
 455                 return -ENOMEM;
 456         uref = &uref_multi->uref;
 457         if (cmd == HIDIOCGUSAGES || cmd == HIDIOCSUSAGES) {
 458                 if (copy_from_user(uref_multi, user_arg,
 459                                    sizeof(*uref_multi)))
 460                         goto fault;
 461         } else {
 462                 if (copy_from_user(uref, user_arg, sizeof(*uref)))
 463                         goto fault;
 464         }
 465
 466         switch (cmd) {
 467         case HIDIOCGUCODE:
 468                 rinfo.report_type = uref->report_type;
 469                 rinfo.report_id = uref->report_id;
 470                 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
 471                         goto inval;
 472
 473                 if (uref->field_index >= report->maxfield)
 474                         goto inval;
 475
 476                 field = report->field[uref->field_index];
 477                 if (uref->usage_index >= field->maxusage)
 478                         goto inval;
 479
 480                 uref->usage_code = field->usage[uref->usage_index].hid;
 481
 482                 if (copy_to_user(user_arg, uref, sizeof(*uref)))
 483                         goto fault;
 484
 485                 goto goodreturn;
 486
 487         default:
 488                 if (cmd != HIDIOCGUSAGE &&
 489                     cmd != HIDIOCGUSAGES &&
 490                     uref->report_type == HID_REPORT_TYPE_INPUT)
 491                         goto inval;
 492
 493                 if (uref->report_id == HID_REPORT_ID_UNKNOWN) {
 494                         field = hiddev_lookup_usage(hid, uref);
 495                         if (field == NULL)
 496                                 goto inval;
 497                 } else {
 498                         rinfo.report_type = uref->report_type;
 499                         rinfo.report_id = uref->report_id;
 500                         if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
 501                                 goto inval;
 502
 503                         if (uref->field_index >= report->maxfield)
 504                                 goto inval;
 505
 506                         field = report->field[uref->field_index];
 507
 508                         if (cmd == HIDIOCGCOLLECTIONINDEX) {
 509                                 if (uref->usage_index >= field->maxusage)
 510                                         goto inval;
 511                         } else if (uref->usage_index >= field->report_count)
 512                                 goto inval;
 513
 514                         else if ((cmd == HIDIOCGUSAGES || cmd == HIDIOCSUSAGES) &&
 515                                  (uref_multi->num_values > HID_MAX_MULTI_USAGES ||
 516                                   uref->usage_index + uref_multi->num_values > field->report_count))
 517                                 goto inval;
 518                 }
 519
 520                 switch (cmd) {
 521                 case HIDIOCGUSAGE:
 522                         uref->value = field->value[uref->usage_index];
 523                         if (copy_to_user(user_arg, uref, sizeof(*uref)))
 524                                 goto fault;
 525                         goto goodreturn;
 526
 527                 case HIDIOCSUSAGE:
 528                         field->value[uref->usage_index] = uref->value;
 529                         goto goodreturn;
 530
 531                 case HIDIOCGCOLLECTIONINDEX:
 532                         i = field->usage[uref->usage_index].collection_index;
 533                         kfree(uref_multi);
 534                         return i;
 535                 case HIDIOCGUSAGES:
 536                         for (i = 0; i < uref_multi->num_values; i++)
 537                                 uref_multi->values[i] =
 538                                     field->value[uref->usage_index + i];
 539                         if (copy_to_user(user_arg, uref_multi,
 540                                          sizeof(*uref_multi)))
 541                                 goto fault;
 542                         goto goodreturn;
 543                 case HIDIOCSUSAGES:
 544                         for (i = 0; i < uref_multi->num_values; i++)
 545                                 field->value[uref->usage_index + i] =
 546                                     uref_multi->values[i];
 547                         goto goodreturn;
 548                 }
 549
 550 goodreturn:
 551                 kfree(uref_multi);
 552                 return 0;
 553 fault:
 554                 kfree(uref_multi);
 555                 return -EFAULT;
 556 inval:
 557                 kfree(uref_multi);
 558                 return -EINVAL;
 559         }
 560 }
 561
 562 static noinline int hiddev_ioctl_string(struct hiddev *hiddev, unsigned int cmd, void __user *user_arg)
 563 {
 564         struct hid_device *hid = hiddev->hid;
 565         struct usb_device *dev = hid_to_usb_dev(hid);
 566         int idx, len;
 567         char *buf;
 568
 569         if (get_user(idx, (int __user *)user_arg))
 570                 return -EFAULT;
 571
 572         if ((buf = kmalloc(HID_STRING_SIZE, GFP_KERNEL)) == NULL)
 573                 return -ENOMEM;
 574
 575         if ((len = usb_string(dev, idx, buf, HID_STRING_SIZE-1)) < 0) {
 576                 kfree(buf);
 577                 return -EINVAL;
 578         }
 579
 580         if (copy_to_user(user_arg+sizeof(int), buf, len+1)) {
 581                 kfree(buf);
 582                 return -EFAULT;
 583         }
 584
 585         kfree(buf);
 586
 587         return len;
 588 }
 589
 590 static long hiddev_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 591 {
 592         struct hiddev_list *list = file->private_data;
 593         struct hiddev *hiddev = list->hiddev;
 594         struct hid_device *hid;
 595         struct hiddev_collection_info cinfo;
 596         struct hiddev_report_info rinfo;
 597         struct hiddev_field_info finfo;
 598         struct hiddev_devinfo dinfo;
 599         struct hid_report *report;
 600         struct hid_field *field;
 601         void __user *user_arg = (void __user *)arg;
 602         int i, r = -EINVAL;
 603
 604         /* Called without BKL by compat methods so no BKL taken */
 605
 606         mutex_lock(&hiddev->existancelock);
 607         if (!hiddev->exist) {
 608                 r = -ENODEV;
 609                 goto ret_unlock;
 610         }
 611
 612         hid = hiddev->hid;
 613
 614         switch (cmd) {
 615
 616         case HIDIOCGVERSION:
 617                 r = put_user(HID_VERSION, (int __user *)arg) ?
 618                         -EFAULT : 0;
 619                 break;
 620
 621         case HIDIOCAPPLICATION:
 622                 if (arg < 0 || arg >= hid->maxapplication)
 623                         break;
 624
 625                 for (i = 0; i < hid->maxcollection; i++)
 626                         if (hid->collection[i].type ==
 627                             HID_COLLECTION_APPLICATION && arg-- == 0)
 628                                 break;
 629
 630                 if (i < hid->maxcollection)
 631                         r = hid->collection[i].usage;
 632                 break;
 633
 634         case HIDIOCGDEVINFO:
 635                 {
 636                         struct usb_device *dev = hid_to_usb_dev(hid);
 637                         struct usbhid_device *usbhid = hid->driver_data;
 638
 639                         dinfo.bustype = BUS_USB;
 640                         dinfo.busnum = dev->bus->busnum;
 641                         dinfo.devnum = dev->devnum;
 642                         dinfo.ifnum = usbhid->ifnum;
 643                         dinfo.vendor = le16_to_cpu(dev->descriptor.idVendor);
 644                         dinfo.product = le16_to_cpu(dev->descriptor.idProduct);
 645                         dinfo.version = le16_to_cpu(dev->descriptor.bcdDevice);
 646                         dinfo.num_applications = hid->maxapplication;
 647
 648                         r = copy_to_user(user_arg, &dinfo, sizeof(dinfo)) ?
 649                                 -EFAULT : 0;
 650                         break;
 651                 }
 652
 653         case HIDIOCGFLAG:
 654                 r = put_user(list->flags, (int __user *)arg) ?
 655                         -EFAULT : 0;
 656                 break;
 657
 658         case HIDIOCSFLAG:
 659                 {
 660                         int newflags;
 661
 662                         if (get_user(newflags, (int __user *)arg)) {
 663                                 r = -EFAULT;
 664                                 break;
 665                         }
 666
 667                         if ((newflags & ~HIDDEV_FLAGS) != 0 ||
 668                             ((newflags & HIDDEV_FLAG_REPORT) != 0 &&
 669                              (newflags & HIDDEV_FLAG_UREF) == 0))
 670                                 break;
 671
 672                         list->flags = newflags;
 673
 674                         r = 0;
 675                         break;
 676                 }
 677
 678         case HIDIOCGSTRING:
 679                 r = hiddev_ioctl_string(hiddev, cmd, user_arg);
 680                 break;
 681
 682         case HIDIOCINITREPORT:
 683                 usbhid_init_reports(hid);
 684                 r = 0;
 685                 break;
 686
 687         case HIDIOCGREPORT:
 688                 if (copy_from_user(&rinfo, user_arg, sizeof(rinfo))) {
 689                         r = -EFAULT;
 690                         break;
 691                 }
 692
 693                 if (rinfo.report_type == HID_REPORT_TYPE_OUTPUT)
 694                         break;
 695
 696                 report = hiddev_lookup_report(hid, &rinfo);
 697                 if (report == NULL)
 698                         break;
 699
 700                 usbhid_submit_report(hid, report, USB_DIR_IN);
 701                 usbhid_wait_io(hid);
 702
 703                 r = 0;
 704                 break;
 705
 706         case HIDIOCSREPORT:
 707                 if (copy_from_user(&rinfo, user_arg, sizeof(rinfo))) {
 708                         r = -EFAULT;
 709                         break;
 710                 }
 711
 712                 if (rinfo.report_type == HID_REPORT_TYPE_INPUT)
 713                         break;
 714
 715                 report = hiddev_lookup_report(hid, &rinfo);
 716                 if (report == NULL)
 717                         break;
 718
 719                 usbhid_submit_report(hid, report, USB_DIR_OUT);
 720                 usbhid_wait_io(hid);
 721
 722                 r = 0;
 723                 break;
 724
 725         case HIDIOCGREPORTINFO:
 726                 if (copy_from_user(&rinfo, user_arg, sizeof(rinfo))) {
 727                         r = -EFAULT;
 728                         break;
 729                 }
 730
 731                 report = hiddev_lookup_report(hid, &rinfo);
 732                 if (report == NULL)
 733                         break;
 734
 735                 rinfo.num_fields = report->maxfield;
 736
 737                 r = copy_to_user(user_arg, &rinfo, sizeof(rinfo)) ?
 738                         -EFAULT : 0;
 739                 break;
 740
 741         case HIDIOCGFIELDINFO:
 742                 if (copy_from_user(&finfo, user_arg, sizeof(finfo))) {
 743                         r = -EFAULT;
 744                         break;
 745                 }
 746
 747                 rinfo.report_type = finfo.report_type;
 748                 rinfo.report_id = finfo.report_id;
 749
 750                 report = hiddev_lookup_report(hid, &rinfo);
 751                 if (report == NULL)
 752                         break;
 753
 754                 if (finfo.field_index >= report->maxfield)
 755                         break;
 756
 757                 field = report->field[finfo.field_index];
 758                 memset(&finfo, 0, sizeof(finfo));
 759                 finfo.report_type = rinfo.report_type;
 760                 finfo.report_id = rinfo.report_id;
 761                 finfo.field_index = field->report_count - 1;
 762                 finfo.maxusage = field->maxusage;
 763                 finfo.flags = field->flags;
 764                 finfo.physical = field->physical;
 765                 finfo.logical = field->logical;
 766                 finfo.application = field->application;
 767                 finfo.logical_minimum = field->logical_minimum;
 768                 finfo.logical_maximum = field->logical_maximum;
 769                 finfo.physical_minimum = field->physical_minimum;
 770                 finfo.physical_maximum = field->physical_maximum;
 771                 finfo.unit_exponent = field->unit_exponent;
 772                 finfo.unit = field->unit;
 773
 774                 r = copy_to_user(user_arg, &finfo, sizeof(finfo)) ?
 775                         -EFAULT : 0;
 776                 break;
 777
 778         case HIDIOCGUCODE:
 779                 /* fall through */
 780         case HIDIOCGUSAGE:
 781         case HIDIOCSUSAGE:
 782         case HIDIOCGUSAGES:
 783         case HIDIOCSUSAGES:
 784         case HIDIOCGCOLLECTIONINDEX:
 785                 r = hiddev_ioctl_usage(hiddev, cmd, user_arg);
 786                 break;
 787
 788         case HIDIOCGCOLLECTIONINFO:
 789                 if (copy_from_user(&cinfo, user_arg, sizeof(cinfo))) {
 790                         r = -EFAULT;
 791                         break;
 792                 }
 793
 794                 if (cinfo.index >= hid->maxcollection)
 795                         break;
 796
 797                 cinfo.type = hid->collection[cinfo.index].type;
 798                 cinfo.usage = hid->collection[cinfo.index].usage;
 799                 cinfo.level = hid->collection[cinfo.index].level;
 800
 801                 r = copy_to_user(user_arg, &cinfo, sizeof(cinfo)) ?
 802                         -EFAULT : 0;
 803                 break;
 804
 805         default:
 806                 if (_IOC_TYPE(cmd) != 'H' || _IOC_DIR(cmd) != _IOC_READ)
 807                         break;
 808
 809                 if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGNAME(0))) {
 810                         int len = strlen(hid->name) + 1;
 811                         if (len > _IOC_SIZE(cmd))
 812                                  len = _IOC_SIZE(cmd);
 813                         r = copy_to_user(user_arg, hid->name, len) ?
 814                                 -EFAULT : len;
 815                         break;
 816                 }
 817
 818                 if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGPHYS(0))) {
 819                         int len = strlen(hid->phys) + 1;
 820                         if (len > _IOC_SIZE(cmd))
 821                                 len = _IOC_SIZE(cmd);
 822                         r = copy_to_user(user_arg, hid->phys, len) ?
 823                                 -EFAULT : len;
 824                         break;
 825                 }
 826         }
 827
 828 ret_unlock:
 829         mutex_unlock(&hiddev->existancelock);
 830         return r;
 831 }
 832
 833 #ifdef CONFIG_COMPAT
 834 static long hiddev_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 835 {
 836         return hiddev_ioctl(file, cmd, (unsigned long)compat_ptr(arg));
 837 }
 838 #endif
 839
 840 static const struct file_operations hiddev_fops = {
 841         .owner =        THIS_MODULE,
 842         .read =         hiddev_read,
 843         .write =        hiddev_write,
 844         .poll =         hiddev_poll,
 845         .open =         hiddev_open,
 846         .release =      hiddev_release,
 847         .unlocked_ioctl =       hiddev_ioctl,
 848         .fasync =       hiddev_fasync,
 849 #ifdef CONFIG_COMPAT
 850         .compat_ioctl   = hiddev_compat_ioctl,
 851 #endif
 852         .llseek         = noop_llseek,
 853 };
 854
 855 static char *hiddev_devnode(struct device *dev, mode_t *mode)
 856 {
 857         return kasprintf(GFP_KERNEL, "usb/%s", dev_name(dev));
 858 }
 859
 860 static struct usb_class_driver hiddev_class = {
 861         .name =         "hiddev%d",
 862         .devnode =      hiddev_devnode,
 863         .fops =         &hiddev_fops,
 864         .minor_base =   HIDDEV_MINOR_BASE,
 865 };
 866
 867 /*
 868  * This is where hid.c calls us to connect a hid device to the hiddev driver
 869  */
 870 int hiddev_connect(struct hid_device *hid, unsigned int force)
 871 {
 872         struct hiddev *hiddev;
 873         struct usbhid_device *usbhid = hid->driver_data;
 874         int retval;
 875
 876         if (!force) {
 877                 unsigned int i;
 878                 for (i = 0; i < hid->maxcollection; i++)
 879                         if (hid->collection[i].type ==
 880                             HID_COLLECTION_APPLICATION &&
 881                             !IS_INPUT_APPLICATION(hid->collection[i].usage))
 882                                 break;
 883
 884                 if (i == hid->maxcollection)
 885                         return -1;
 886         }
 887
 888         if (!(hiddev = kzalloc(sizeof(struct hiddev), GFP_KERNEL)))
 889                 return -1;
 890
 891         init_waitqueue_head(&hiddev->wait);
 892         INIT_LIST_HEAD(&hiddev->list);
 893         spin_lock_init(&hiddev->list_lock);
 894         mutex_init(&hiddev->existancelock);
 895         hid->hiddev = hiddev;
 896         hiddev->hid = hid;
 897         hiddev->exist = 1;
 898         retval = usb_register_dev(usbhid->intf, &hiddev_class);
 899         if (retval) {
 900                 hid_err(hid, "Not able to get a minor for this device\n");
 901                 hid->hiddev = NULL;
 902                 kfree(hiddev);
 903                 return -1;
 904         }
 905         return 0;
 906 }
 907
 908 /*
 909  * This is where hid.c calls us to disconnect a hiddev device from the
 910  * corresponding hid device (usually because the usb device has disconnected)
 911  */
 912 static struct usb_class_driver hiddev_class;
 913 void hiddev_disconnect(struct hid_device *hid)
 914 {
 915         struct hiddev *hiddev = hid->hiddev;
 916         struct usbhid_device *usbhid = hid->driver_data;
 917
 918         mutex_lock(&hiddev->existancelock);
 919         hiddev->exist = 0;
 920
 921         usb_deregister_dev(usbhid->intf, &hiddev_class);
 922
 923         if (hiddev->open) {
 924                 usbhid_close(hiddev->hid);
 925                 wake_up_interruptible(&hiddev->wait);
 926         } else {
 927                 kfree(hiddev);
 928         }
 929         mutex_unlock(&hiddev->existancelock);
 930 }